The present invention relates to the fabrication of three-dimensional (3D) objects using layered deposition systems. In particular, the present invention relates to syringe tip assemblies for use with syringe-based, layered deposition systems.
A layered deposition system is used to build a 3D object from a computer-aided design (CAD) model in a layer-by-layer manner by depositing a flowable build material. The build material is deposited from a deposition head as a sequence of roads on a substrate in an x-y plane. The deposited build material fuses to previously deposited build material and solidifies. The position of the deposition head relative to the base is then incremented along a z-axis (perpendicular to the x-y plane), and the process is then repeated to form a 3D object resembling the CAD model. Movement of the deposition head with respect to the base is performed under computer control, in accordance with build data that represents the 3D object. The build data is obtained by initially slicing the CAD model of the 3D object into multiple horizontally sliced layers. Then, for each sliced layer, the host computer generates a build path for depositing roads of build material to form the 3D object.
One type of deposition head for use with layered deposition systems is a syringe deposition tool. The syringe deposition tool extrudes build material through a syringe tip with the use of a motor-powered syringe piston. However, syringe deposition tools typically have poor flow control, which result in low-quality seams, and are difficult control over the start and stop times due to relatively slow response times. As such, there is a need for a system and method for improving the flow control of syringe deposition tools.